Bow front will add a magnifying glass effect. Its kinda cool in some ways. But in other ways it isnt.You just have to decide which would suit you.
As for sump, you can get away w/out a sump.
An HOB fuge/skimmer would work just fine.
An external canister like a fluvial or something to that effect would also do plenty. And would save you the hassle of a sump.
Other things you can look into that would still be compatible with an HOB type setup would be a small UV system, or a Carbon/GFO reactor. The pumps needed to power these would be sitting in your HOB and the discharge would also drain right back into it.
That said, you will have more options if decide to add a sump.
For starters like the above poster mentioned, you will have more filtration options. Also more water volume means more success/forgivness. I could go on, but you get the idea.
In short, if you can feasibly do a sump style setup, by all means go ahead, it will only do good things. And if you ever decide to go from FOWLR to REEF, the transition will be extremely easy.Pretty much adding proper lights up top and your done.
